! Proposal 6567, submission 1 ! PI: Luciana Bianchi ! Received Fri Feb 9 11:44:56 EST 1996 ! From: bianchi@stsci.edu !%From: STSCIC::IN%"dctaylor@stsci.edu" "Denise Taylor" 5-JAN-1996 11:00:39.62 !%To: IN%"bianchi@stsci.edu" !%CC: IN%"dctaylor@stsci.edu", IN%"keyes@stsci.edu" !%Subj: Phase II Template for HST Proposal 6567 !%Congratulations on being awarded 30 primary orbits and 5 parallel! !% Winds of massive stars in nearby galaxies: NGC6822 !%This proposal has been assigned ID number 6567. Please refer to this !%Your Phase II submission due date is February 16, 1996. !%Your primary STScI Support Team (please see details below) is !% Program Coordinator: Denise Taylor (dctaylor@stsci.edu) !% Contact Scientist : Tony Keyes (keyes@stsci.edu) !%Backup STScI contact at all times is help@stsci.edu. !Questions concerning the actual writing and submission of your program !should be directed to Denise Taylor, whereas questions concerning the !scientific content of your program, technical feasibility, assessment !of your data quality, and any other aspect of post-observation !analysis of your data should be handled by Tony Keyes. Please feel !free to contact us if you need help with any aspect of your Cycle 6 !HST observing program. We will be contacting you throughout this !process to keep you informed about the status of your program and to !make you aware of any issues that impact it. !%Denise Taylor (Program Coordinator) (dctaylor@stsci.edu, 410-338-4824) !%Tony Keyes (Contact Scientist) (keyes@stsci.edu, 410-338-4975) ! Hubble Space Telescope Cycle 6 (1996) Phase II Proposal Template ! $Id: 6567,v 18.1 1996/07/11 19:26:44 pepsa Exp $ ! Hubble Space Telescope Cycle 6 (1996) Phase II Proposal Template ! $Id: 6567,v 18.1 1996/07/11 19:26:44 pepsa Exp $ ! ! Refer to the HST Phase II Proposal Instructions to fill this out ! ! Anything after a "!" is ignored, and may be deleted ! ! All keywords with multiple entries are comma delimited except the ! Visit_Requirements and Special_Requirements keywords which can be ! delimited with carriage returns or semi-colons, but not commas ! ! For help call your Program Coordinator: Taylor ! Phone: 410-338-4824 , E-mail: dctaylor@stsci.edu ! ! This partially completed template was generated from a Phase I proposal. ! Name of Phase I Proposal: archive-0447.bianchi.prop ! Date generated: Fri Dec 22 18:35:32 EST 1995 ! Proposal_Information ! Section 4 Title: Winds of massive stars in nearby galaxies: NGC6822 Proposal_Category: GO Scientific_Category: HOT STARS Cycle: 6 Investigators PI_name: Luciana Bianchi PI_Institution: Space Telescope Science Institute CoI_Name: Salvatore Scuderi CoI_Institution: Space Telescope Science Institute Contact: ! Y or N (designate at most one contact) CoI_Name: John Hutchings CoI_Institution: Dominion Astrophysical Observatory Contact: ! Y or N (designate at most one contact) CoI_Name: Philip Massey CoI_Institution: National Optical Astronomy Observatories Contact: ! Y or N (designate at most one contact) CoI_Name: Arturo Manchado-Torres CoI_Institution: Instituto de Astrofisica de Canarias Contact: ! Y or N (designate at most one contact) CoI_Name: Ralph Bohlin CoI_Institution: Space Telescope Science Institute Contact: ! Y or N (designate at most one contact) CoI_Name: Henny Lamers CoI_Institution: SRON -Utrecht Contact: ! Y or N (designate at most one contact) Abstract: ! Free format text (please update) In cycle 1 and cycle 4 we obtained FOS spectra of individual early type stars in M31 and M33. Combined with ground based data, the UV spectra were used to study stellar atmospheres and winds and compare wind velocities, mass loss rates, and abundances with similar galactic and LMC stars. We analysed the data by modeling line profiles with different methods, and made direct comparison between spectra of similar stars in different galaxies. Detailed study of hot star populations in galaxies outside the Milky Way provides a very important test of theories of stellar winds, star formation and evolution. Extinction properties of the ISM in the UV are also derived from the continuum distribution. We propose to extend these comparisons to the Local Group irregular galaxy NGC6822. Here the foreground extinction poses more severe limitations than in M31 and M33, but we have found 5 targets, from extensive optical work (Massey et al.1995), that are accessible to FOS/GHRS and will provide a small but highly valuable exploratory sample. Our ground based spectroscopy indicates that the metal lines in NGC6822 B-supergiants are significantly weaker than in SMC stars of similar spectral type and luminosity, which is inconsistent with the considerably higher than SMC-like metallicity indicated by HII region studies. HST spectroscopy in the UV provides valuable information about the metallicity. Questions ! Free format text (please update) Observing_Description: In order to fit the continuum and derive extinction, temperature, and luminosity, we require the range 1200- 3300Angstrom. This range will also contain all the wind and photospheric lines, below 1900Angstrom. We propose to observe with the GHRS+G140L, FOS/BL G190H and G270H. Using GHRS in the shorter wavelength range gives better resolution and efficiency just in the region where the strong wind line of NV 1240 (and CII, OIV) are poorly covered by the FOS-G130H. From recent figures, we find that GHRS is more sensitive by a factor from 6.4 to 1.3, from NV 1250 to CIV1550 (after degrading the data to the same resolution of the FOS/BL- G130H). FOS is more efficient for the longer wavelengths but also for the acquisition, which can then be offset to the GHRS with no additional time consuming target acquisition. We tested and successfully used this procedure during cycle 5. The targets are selected from the brightest and hottest stars known in this galaxy. We have optical CCD photometry and spectra. These data combined allow us to establish spectral type, luminosity class, magnitude, colors, and extinction, to compute exposure times. To model wind and photospheric line profiles we require a S/N in the 1200-1900Angstrom range not less than 15 per Angstrom. Each exposure may be split into several integrations that will be co-added to reach the required S/N. The exposure times are calculated on the basis of the ground based photometry, spectral type and extinction, and on the performance of the instruments estimated from our Cycle 4 observations and from the Cycle 6 instructions. In the G190H, and especially in the G270H range, we are mainly interested in the continuum distribution, therefore, in the interest of time, a S/N of 20 for continuum fitting in broad bands of 25Angstrom for the fainter stars is adequate. In this way, the exposures in the FOS G190H and G270H in most cases both fit into the first orbit with the acquisition and the readouts. The GHRS exposures require two orbits for each setting (two settings are needed to cover all the wind lines of interest: 1200- 1483Angstrom, and 1480-1760Angstrom). Target acquisition has worked very well in the past, in the FOS 1'' aperture (binary acquisition) for the M31 and M33 stars. We chose well isolated objects, so we can use the GHRS large (1.7'') aperture. While our ground-based photometry and spectra identify our proposed program stars as good candidates, and guarantee safe acquisitions and spectrographic exposures, the errors on ground based photometry are quite large, from the point of view of the analysis. In fact, not only are the stars very faint, but hot stars are usually embedded in bright nebulosity. In the extraction of the point-like stellar flux from the surrounding diffuse emission, a greatest improvement can be achieved from HST imaging, resulting in a substantially better determination of some stellar quantities. This will also add a further, more conclusive, check on the isolation of the objects and will therefore provide extra safety on the HST spectroscopy execution. Thus, we also propose to obtain images to obtain accurate single star photometry, before the spectrographic observations are done. The entire area of all our program stars fits within only two WFPC2 images, so only two orbits are needed, to improve the science and make the observations much more efficient and the acquisitions more reliable. We request WFPC2 pointings at 2 positions that will include all our stars, obtaining short exposures with the U, B, V filters in each position. As a secondary goal, we request PC images parallel to the FOS spectra, with the F336W and V filters, to select UV-bright objects for follow up work from the ground (photometry and spectroscopy) as a prelude to possible additional HST work, and to complement the UBV photometry done from the ground, and proposed with HST in this cycle by one of us (PM) in a related proposal. The V-band is necessary for linking with the ground-based imaging, and to assess possible multiplicity of a large number of stars. In the UV, detection of even a small number of objects will be very important, as these can be the most massive ones. The high quality of the refurbished HST imaging will yield unprecedented information on these crowded fields, as demonstrated by our Cycle 4 parallel images taken recently. Our positions have been measured on CCD frames taken at KPNO (so with a recent epoch) and reduced in the GSC reference system. The targets are too faint to be measurable on the GASP frames. The fields are rather crowded, but we checked that in the cases proposed, there is no contamination by other target within 2 arcsec. This worked well in previous cycles in our M31 and M33 programs. Real_Time_Justification: The WFPC2 images (non parallel) should be performed at a given roll angle to include all the targets in two pointings only. One of us (PM) has obtained extensive optical observations of stars in NGC6822, providing the identification of the most luminous and hottest stars and an accurate determination of sp.type, extinction, T_eff, L_bol. These results provided the basis for the presently proposed research. Also, we have planned WHT observations (high resolution, long slit) of the Balmer lines, to complement the UV FOS spectral line analysis, as we have done for our M31 and M33 targets, and described in the previous section. Complementary observations are also continuing at KPNO. Calibration_Justification: ! Move appropriate text from Real_Time_Justification Additional_Comments: Fixed_Targets ! Section 5.1 !****************************TARGETS*********************** Target_Number: 1 Target_Name: NGC6822-OB15-9 Alternate_Names: Description: EXT-STAR, B0-B2 III-I Position: RA=19H 45M 13.35S +/- 1",DEC=-14D 45' 07.9" +/-1",PLATE-ID=00CN Equinox: 2000. RV_or_Z: RA_PM: ! Units are seconds of time per year Dec_PM: ! Units are seconds of arc per year Epoch: Annual_Parallax: Flux: V=18.08 +/-0.2, U-B=-0.78+/-.4, B-V=-0.02+/-.4 Comments: E(B-V)=0.17 Target_Number: 2 Target_Name: NGC6822-OB13-9 Alternate_Names: Description: EXT-STAR,Supergiant O Position:RA=19H 45M 05.35S +/- 1", DEC=-14D 43' 12.3" +/-1",PLATE-ID=00CN Equinox: 2000. RV_or_Z: RA_PM: ! Units are seconds of time per year Dec_PM: ! Units are seconds of arc per year Epoch: Annual_Parallax: Flux: V=18.08+/-0.2, U-B=-0.76+/-.4, B-V=-0.08+/-.4 Comments: E(B-V)=0.22, EARLY O Target_Number: 3 Target_Name: NGC6822-OB8F-2 Alternate_Names: Description: EXT-STAR, B0-B2 III-I Position: RA=19H 44M 50.30S +/- 1", DEC=-14D 42' 53.4" +/- 1", PLATE-ID=00CN Equinox: 2000 RV_or_Z: RA_PM: ! Units are seconds of time per year Dec_PM: ! Units are seconds of arc per year Epoch: Annual_Parallax: Flux: V=16.92+/-.2, U-B=-0.68 +/-.4, B-V=-0.21 +/-.4 Comments: B1.5III, E(B-V)=0.38 Target_Number: 4 Target_Name: NGC6822-OB6-16 Alternate_Names: Description:EXT-STAR,Supergiant O Position: RA=19H 44M 49.41S +/- 1",DEC=-14D 44' 03.9" +/- 1",PLATE-ID=00CN Equinox: 2000 RV_or_Z: RA_PM: ! Units are seconds of time per year Dec_PM: ! Units are seconds of arc per year Epoch: Annual_Parallax: Flux: V=18.11 +/-0.3, U-B=-0.82 +/-.4, B-V=0.10 +/-.4 Comments: O9II, E(B-V)=0.37 Target_Number: 5 Target_Name: NGC6822-OB7-15 Alternate_Names: Description: EXT-STAR, B0-B2 III-I Position: RA=19H 44M 49.12S +/- 1", DEC=-14D 45' 26.6" +/- 1",PLATE-ID=00CN ! Most common specification format is ! RA=0H 0M 0.00S +/- 0S, ! DEC=0D 0' 0.0" +/- 0", ! PLATE-ID=0000 Equinox: 2000. RV_or_Z: RA_PM: ! Units are seconds of time per year Dec_PM: ! Units are seconds of arc per year Epoch: Annual_Parallax: Flux: V= 17.50 +/-0.03, U-B=-0.73+/-.4, B-V=0.16 +/-.4 Comments: EARLY B, E(B-V)=0.35 Target_Number: 6 Target_Name: NGC6822-OB6-OB7 Alternate_Names: Description: EXT-CLUSTER, OB Association Position: RA= 19H 45M 08S +/- 1", DEC=-14D 44' 27.6"+/- 1", PLATE-ID=00CN Equinox: 2000. RV_or_Z: RA_PM: ! Units are seconds of time per year Dec_PM: ! Units are seconds of arc per year Epoch: Annual_Parallax: Flux: V=16 +/-0.03, B-V=0.2 +/-.4 !THIS WILL BE TYPICALLY THE BRIGHTEST Comments: CONTAINS TARGETS 1,2 !if done in june WITH U3=225 ! SECOND CHOICE: NONE Target_Number: 7 Target_Name: NGC6822-OB13-OB15-OB8 Alternate_Names: Description: EXT-CLUSTER, OB Association Position: RA=19H 44M 49S+/- 1", DEC=-14D 44' 00"+/- 1", PLATE-ID=00CN Equinox: 2000 RV_or_Z: RA_PM: ! Units are seconds of time per year Dec_PM: ! Units are seconds of arc per year Epoch: Annual_Parallax: Flux: V=16 +/-0.03, B-V=0.2 +/-.4 !THIS WILL BE TYPICALLY THE BRIGHTEST Comments: CONTAINS TARGETS 3,4,5 !IF OBSERVED IN APRIL 96 W/U3=280 (+20 FROM NOMINAL ROLL) ! SECOND CHOICE: U3=280 IN JUNE WITH 30D DEVIATION FROM NOMINAL ! THRID CHOICE: U3=100 IN AUG. WITH NO DEVIATION !====================================================================== Generic_Targets ! Section 5.3 Target_Number: 8 Target_Name: NGC6822-PAR1 Description: EXT-CLUSTER, OB Association Criteria: WILL BE THE WFPC2 POSITION DURING FOS EXPOSURE IN VISIT 1 Flux: V=16 +/-0.03, B-V=0.2 +/-.4 !THIS WILL BE TYPICALLY THE BRIGHTEST Comments: PARALLEL TO FOS OBSERVATION OF TARGET 1 Target_Number: 9 Target_Name: NGC6822-PAR2 Description: EXT-CLUSTER, OB Association Criteria: WILL BE THE WFPC2 POSITION DURING FOS EXPOSURE IN VISIT 2 Flux: V=16 +/-0.03, B-V=0.2 +/-.4 !THIS WILL BE TYPICALLY THE BRIGHTEST Comments: PARALLEL TO FOS OBSERVATION OF TARGET 2 Target_Number: 10 Target_Name: NGC6822-PAR3 Description: EXT-CLUSTER, OB Association Criteria: WILL BE THE WFPC2 POSITION DURING FOS EXPOSURE IN VISIT 3 Flux: V=16 +/-0.03, B-V=0.2 +/-.4 !THIS WILL BE TYPICALLY THE BRIGHTEST Comments:PARALLEL TO FOS OBSERVATION OF TARGET 3 Target_Number: 11 Target_Name: NGC6822-PAR4 Description: EXT-CLUSTER, OB Association Criteria: WILL BE THE WFPC2 POSITION DURING FOS EXPOSURE IN VISIT 4 Flux: V=16 +/-0.03, B-V=0.2 +/-.4 !THIS WILL BE TYPICALLY THE BRIGHTEST Comments: PARALLEL TO FOS OBSERVATION OF TARGET 4 Target_Number: 12 Target_Name: NGC6822-PAR5 Description: EXT-CLUSTER, OB Association Criteria: WILL BE THE WFPC2 POSITION DURING FOS EXPOSURE IN VISIT 5 Flux: V=16 +/-0.03, B-V=0.2 +/-.4 !THIS WILL BE TYPICALLY THE BRIGHTEST Comments: PARALLEL TO FOS OBSERVATION OF TARGET 5 !Scan_Data ! Appendix B ! Scan_Number: ! FGS_Scan: ! Cont_or_Dwell: ! Dwell_Points: ! Dwell_Secs: ! Scan_Width: ! Scan_Length: ! Sides_Angle: ! Number_Lines: ! Scan_Rate: ! First_Line_PA: ! Scan_Frame: ! Length_Offset: ! Width_Offset: ! This is a template for a single visit containing a single exposure ! Repeat exposure and visit blocks as needed Visits ! Section 6 !*************************VISIT1****************************************** Visit_Number: 1 Visit_Requirements: ORIENT 265D TO 269D !U3 P.A. (IDEAL V3=80) ! Section 7.1 ! Uncomment or copy visit level special requirements needed ! Most of these requirements (including ORIENT) will limit scheduling ! PCS MODE [Fine | Gyro] ! GUIDing TOLerance ! DROP TO GYRO IF NECESSARY [NO REACQuisition] ! ORIENTation TO ! ORIENTation TO FROM ! ORIENTation TO FROM NOMINAL ! SAME ORIENTation AS ! CVZ ! PARallel ! SCHEDulability ! AFTER [BY [TO ]] ! AFTER ! BEFORE ! BETWEEN AND ! GROUP WITHIN